Disable the keyboard when the keyboard listeners have detached
Added widget-level Keys and Modifiers callbacks
Make ToggledEvent not implicitly set Callbacks

In practice, everywhere this function is used will set Callbacks, but I
prefer keeping functions as single-responsibility as possible.
minor alias
Call EnableMouse to detect OnEnter, OnLeave
Support Recall.Value, Global
Use our filter once again for XML files (fixes a WoW bug)
Added Anchors.Origin, to determine the origin for different platforms
Use Anchors.Origin instead of inlining platforms
Added Anchors.Absolute
Pass along mouse arguments
Don't call naked requires (for WoW compat)
Support custom parsers for LuaEnvironment

This is sort-of an intermediate step, but custom parsers add an incredible
amount of functionality. However, in doing so, the process drifts away from
being a *Lua*Environment to just being an environment. This is probably
how it should be.
Support OnMouseMove
Ignore spurious flush requests
Don't attempt to override basic functions

Most functions in Fritomod can ruthlessly override others without
causing problems, but these are quite fundamental, so it's important to
only implement them if necessary. platform, POISON, and Noop are
especially important.
Added initial JSON support
Support byte-size color values